You are a small cog in a money-making machine, not a human being
Pros
There's a 15% furniture discount for employees, and they offer health and retirement benefits. I can't think of anything else beyond that.
Cons
IKEA has notoriously terrible management, partially because they pay employees a very low starting wage, so the few people who stay around long enough to make it to managerial level are the ones who couldn't get a job anywhere else. Also, it's challenging for employees to take personal ownership of their workplace because all decisions are made high above in Sweden, so each individual's job is essentially to carry out those specifics, don't deviate from the masterplan, and don't work overtime for ever one minute without supervisor approval. They're so fascist, that clocking at 7:01am for a 7:00am shift start is considered late and goes on your 3-strikes record. Even if there were 10 people clocking in ahead of you. It's this kind of unyielding, inflexible mentality that makes great people with great ideas want to steer clear of working at IKEA. Keep in mind, you are simply a tool for keeping the store organized, not for helping customers or going out of your way to do the right thing.