There are a lot of reasons why bowling sucks:
Its bloody hard work.
You will be injured, no exceptions.
The batsmen get all the glory.
For the batsman every run counts (statistically). The bowler might bowl brilliantly but there won't necessarily be statistics to prove his brilliance.
But, every run counts ... against you.
Even if you get the batsmen to hit a catch, the fieldsman might not catch it.
The LBW law. OK, the batsman has to stand somewhere, but he's got a fucking bat.
Even if you get a bloke plumb LBW, the umpire might not give it.
Its a batsmen's game with not only all the rules, but the unwritten conventions, in the batsman's favour.
The bats get better, the ball stays the same.
In international cricket they have flat, flat decks.
You have to do that weird jumpy, spinny, dancey thing with the whirly arms (ie the bowling action).
You look a bit silly doing that.
You are not allowed to just chuck it like a normal person would.
Err ... even though it has been scientifically proven that basically everybody does chuck it to some degree.
Horses for courses means you might get dropped on a certain type of wicket - but they don't treat the batsmen like horses.
And absolute worst of all ...
This is how you bat: Watch the ball, hit the ball. That's it. The ball. Not the bowler.
This is how you bowl: Put the ball in exactly the place the batsman doesn't want it. Each batsman. Individually. No standard plan, no consistent approach. Every bloke you come up against watch his technique, know his mindset, find his flaws. And then work away at that until you get him out. Then do it again with a different bloke that has a completely different technique, mindset etc. Each new opponent requires you to put the ball somewhere totally different to the last bloke.
Meanwhile that bloke just watches the ball, hits the ball, no matter who you are. They don't really care who you are.