Why not? Granted I only get through 1 or 2 books a month, but it's a minuscule part of my budget. I can't say I've looked into it, but I assume it's also the best way to actually support the author.
I'm not sure if you have to have donated before or not but i did and they gave me a link to the bot.. it works like irc where you just give it words and it returns results with links you can click to start the xfer over telegram