I do not think game it's really expensive, we're talking about 25 and some plugins you can buy around at cost of 15 for a plugin... it's not the best game at market now, but still worth price per time, Minecraft give a lot of hours of fun, and a lot of "Good games" with 60 value you can finish it in less that 40 hours. so... No, it's not expensive.
It's fine IMHO. Especially since you have to pay for it only once, there are no monthly fees, at least not on PC. It's not like World of Warcraft, where you have to pay a shit-ton to buy all the expansions, and on top of that, pay $10 a month or so to play.