Mountain Biking

Hi everyone, I am a beginner with MTB. I just recently got a polygon T6 and have been loving it. I'm doing research about all the new aspects with MTB and quickly finding out how pricey this hobby can be. My boss recommended that I get specific shoes made for MTB. I did a quick search to find that they are really expensive. My question is: are these necessary? Or can I find a good pair of skate shoes for a cheaper price? I don't do hardcore riding yet and only go a few hours a week.

EDIT: thanks everyone for the responses. I will keep shoes on my to buy list, but I will wait a little until I find a good deal.