Actually, you can set a non-Dashboard homepage from within Tear. Using the menu, go to Tools >> Options. This has the advantage that when you click the + next to the address bar, it pops up a new window that's using your homepage.

Nonetheless, sometimes I'm on a webpage and would like to go to my homepage (which is Google Bookmarks) in that same window (rather than bother with closing that window after opening a new one) and it would be quicker if I could get to the bookmark for my homepage with one less click.