I purchased a theme just over a year ago… and never got it to function properly. They game me a full Credit! (Ohhhh the wasted hours leading to depression) So I used the credit to buy a new theme and a slider. The confirmation email says I owe Install fees!!! Really?
While I totally understand why you are upset, for issues that are specific to your account/payments/purchases, I’d reccommend contacting Envato Help&Support team, opening a help ticket on this page: https://help.market.envato.com/hc/en-us/requests/new (and use the select box at the bottom of the page, where it says “Submit your request”) The support team has access to your account/purchases and can help with more detailed feedback & support.
I’m guessing, you’re referring to Installing service. Studio service fee is different than theme fee. You don’t need to purchase the service if you can install it by yourself.