That's very true. I'm actually very curious about how LEGO Dimensions is going to work out, in that regard. LEGO has a pretty substantial history with both the Marvel and Star Wars brands, but the whole "collect and play" genre that they're a part of puts them in, almost, direct competition with Disney Infinity. Personally, though, I think both styles are unique enough that I don't think it would really hurt either one, if people already have Infinity.
Hell, they could, potentially, make twice as much, with two products on the market, but I don't think they will, for the sake of the universe, as the sheer awesomeness of Batman, Marty Mcfly, Captain America, Gandalf, Doctor Who, and the Ghostbusters (a lot of speculation attached to the PKE meter in the first trailer/the fact that they were able to get the license for that LEGO Ideas Ecto-1) flying around Springfield in the Millenium Falcon, with Han and Chewie at the helm, would, undoubtedly, cause it to explode.