Sure you can. You use whatever you think looks good, whether that's something cheap from Ikea or an Eames Lounge chair?
Of course you can. You can use whatever you want in your apartment if you think it looks good or suits you. My apartment is filled with Ikea and Super A-Mart stuff. And I don't care because I don't pretend to be a pretentious connoisseur. I use prints, unique rugs and local-sourced art to tie things together, and it works.
But you have to have to call a spade a spade and realise that your apartment is still filled with Ikea.
Ikea is made from plywood, pleather and all manner of cheap materials.
It's also mass manufactured to all hell.
For $500 you can have a loungeroom that looks exactly like Mrs Jenkins' next door.
A connoisseur will have tables made from actual wood. Couches made with actual leather. And more often than not will look for unique and often imported and hard to get furniture and lounge pieces. Sculptures and expensive centre pieces that tie a room together with a mood or theme.
If you can't tell the difference between quality materials and unique pieces, and cheap mass-manufactured furniture, then you're anything BUT a connoisseur.
You're a pleb.
Own it.
Now that you've been educated, sit back and think about it and leave yesterday where it belonged.