No, the main difference will not be just average FPS. PC's also tend to run games at settings consoles can't reach. So aside from getting higher FPS, PC's also get higher resolutions, better textures, better post-processing, etc. In the end, the graphical quality is much higher, specially as time goes on and devs "optimize" games for consoles, which really just means they learn which settings to disable first.
As also mentioned, cost of games is a big difference. Games can cost much, much less on the PC side. Images like
this abound on the internet to prove this.
Also, from that image we can be reminded that PC does not charge you for multiplayer. A pretty fundamental difference overall. Some may try to justify the cost with the bonuses the console manufacturers throw in, though.
Finally, there's the fact that most people who game on a console also have a PC for other uses. Instead of spending $500 on a console and $500 on a PC, one can spend $1000 on the PC and get a better gaming experience while also getting a lot more functionality.
There are plenty more differences one can get into. I'm quite personally opinionated in one camp, as you can probably tell, but I'll let someone else fill in the other side if they so desire.