Let's say you already receive donations for bitcoin, ethereum or litecoin. If you already use your cryptocurrencies to buy steempower why not save on fees and utilize blocktrades?
I'm assuming you already know how to use blocktrades, so you select to send cryptocurrency of your choice and receive steempower. Then you input your steemit username, you can also use vegeta if you want to send to me. (I won't complain)
You will then be given a bitcoin deposit address you can put on the page you would like donations.
If you really want to test it out you can try with these addresses. (They go right to my steempower) :P