Personally, I prefer the sound of a 5000 HP big block MoPar. But, as for bikes, some people have more cash than they know what to do with. Those ones go out and toss away $50K and up to get whatever bike is "trendy" that week.
The rest of us go find a bike (or car/truck for that matter) that has the look we like and solid mechanicals at a price we can afford. After that, it's a small change here, a bigger one there, some bolt-on power, some elbowgrease power, etc. Maybe, My Triumph might eventually cost me as much as a Superduper Wonder Dog shop built custom, but it won't cost me that much all at once. It will fit me perfectly and, because I know the bike intimately inside and out, it is much less likely that I will make a fool of myself trying to do the impossible on it.
By the way, the TPS is probably used because it is a lot simpler than working out the air flow with a MAP sensor, especially when constant vacuum carbs are used.
