I have several poems on poetry.com, and I did buy the first book that published one of my poems. I gave it to my mom, who is my biggest fan. I have never submitted a poem to the site without them wanting to publish it in one of their anthologies. I throw away the offers in the trash. I do get a kick out of their poetry in motion contest, however, where you can possibly win $100 by taking several word tiles and making a 25 word poem. They pick one poem every 24 hours at random times, and send them $100. I play it just for fun occasionally. I have never ordered the mugs with my poems on them, mainly because they are costly. But they do have some neat gift ideas, which anyone into crafts can do much cheaper.
You can publish your poetry on poetry.com, but I don't particularly recommend it.