Well, the Galaxy Audio & Behringer look very similar, but as for the Mackie...
* The Behringer has a whole digital FX section, the Mackie doesn't.
* The Behinger has a USB interface, the Mackie doesn't.
* The Mackie has the Aux section above EQ in the channel strip, the Behringer has it the other (conventional) way round.
* The Behringer has channel comps, the Mackie doesn't.
* The Mackie has a -20db activity LED, the Behringer doesn't.
* The Mackie most bizarrely uses the peak LED to indicate Mute as well - that would really bug me!
* The Behringer allows solo of all 4 Aux sends, the Mackie allows if for only Aux 1 & 2
* The Mackie has a level control for the Tape-in, the Behringer doesn't.
So, other than the fact that they're both budget 16:4:2 compact mixers with 8 mic pres, and have a pretty de-facto layaout for that genre, they're pretty comprehensive set of differentiating features there (and I'm sure there are quite a few more if you dig a little deeper)