I don't think the blue shell is a bad thing, and actually, it does strike me as a pretty convincing allegory for real life, albeit in a slightly different way from how Ian sees it.
In Mario Kart, as in real life, the people who are ahead believe they got there through skill, intelligence and hard work. This simple isn't true. If you can pull into first and get even a semi-decent lead, your victory is practically assured- everyone behind you is caught in a vicious blender of red shells and lightning bolts. Anyone who pulls away from the back is likely to get hit by a rogue shell and dragged right back in. Not so for the player in first. The only red shells he has to deal with are the ones from the driver in second, and due to the way the game gives weaker items to those closer to first, the driver in second will very rarely get a red shell (or any item capable of striking down the first player's by-now formidable lead), and even if someone does end up in second with a red shell or two, it's likely that the player in first has managed to get far enough away that the shell will hit some obstacle on the way. This also makes it easier for the first player to get away in the first place- multiple times I've been in second, hotly on the tail of the player in the lead. We'll all go through an item box, me and first will get trash (which is fair), but then third will get a red shell, and, naturally, hit me with it. All I can do is watch as first pulls further away. Then, next item box, now that I'm in third, I'll get a red shell. At this point, I have to decide whether to hit the guy in second to overtake him- essentially securing the win for the guy in first at this point- or go for the 'good of the people', and attempt an item-less overtake of the guy in second to be within striking distance of the first player. This would maybe be possible, but fourth player got a piranha plant, fifth got a star, sixth got a bullet bill, and I'm being rammed by every one.
It's like real life- the rich get richer, and attribute it to their hard work, not the fact they're only getting further ahead because they're already ahead. I applied to a job earlier this year, a job that offers great entry-level experience and could truly turn someones life around. However, they required a whole mess of medical checks and forms before you could even apply. Coupled with the suit I had to buy (and I went for the absolute cheapest), the application process cost me £300. There are people who can't afford this. So, they're stuck in dead-end jobs, whilst those who can afford it (which, I feel fortunate enough to be able to say, includes me) get access to this incredible opportunity, which could easily lead to a fantastic, successful career. The rich get richer. Of course, they attribute it to their 'hard work', and get pissed when people try and take it away, but, as someone who is himself extremely privileged, I recognize the danger of this mode of thought. It's the same in Mario Kart- I don't want to brag, but I'm very often in first place, and I say: bring on the blue shell. I wish it happened more. Sure, it's easy to act like it's 'unfair' and taking away from your skill, but maybe if you try and think about it from someone else's perspective, you'd see that things, actually, were more unfair before the blue shell than after. Mario Kart offers a unique perspective into this- we've all had matches where we've been hit by an item on the first lap and never been able to recover. It's an important educational experience.
Basically how I feel in life on the opposite end. I am resentful that I am stuck in a job I hate without enough money to move to a job I wanted to do. My back-round is so far removed from what I love, that in order to do it I would have to sacrifice any amount of free time in order to achieve it. My parents aren't computer literate and I had to move out at 16.
The point isn't that I live hard or sleep rough; but that I do not have the knowledge of how to get further than my parameters allow. Something that somebody out in front (in life) already had. Yes, those people work hard, but they still had a strong springboard (like people that get university completely paid for them for example by their parents).
It's like the concept of coming into money. Those in a more privileged state know how to turn money into more money through various deals, savings etc. All I know how to do is leave it in my account which basically accumulates almost no interest.
To bring it back round to your point and MK; Sure, I may get to a little way ahead of the main pack; but never enough to have a true chance at being first.
(On a happier note; in actual Mario Kart I am very good because I spend a lot of my free time gaming; so I can't win in real life but certainly can in games lol).