The only other thing I can think could be a factor is that the Slate may be easier to acquire. If it's easier (generally speaking) to get approved for Slate over Freedom, that could be a reason that people decide to app for that product over the other. I don't know if this is the case though, just throwing out another idea to consider.
This is an interesting point. If one would NEED a balance transfer card, that would indicate that one is carrying a balance somewhere.
Theoretically, this would indicate score suppression under the Fico algorithm. Under that framework, you could theorize the underwriting criteria for the Slate should make allowances for such approvals. If it does NOT, it would render the Slate a Catch-22 situation.
Any Slate approval data points to compare against the Freedoms??
Anecdotally, Slate and Freedom seem to have the same approval and U/W requirements. You can get a Slate with as little as $500 for a starting limit, or a starting limit over $10K. It all depends on what your profile supports.
If the Slate were a Rinse and Reuse BT card.. with an offer from time to time for a low apr no fee transfer or a low fee 0% transfer.... it would make a bit more sense to me... Least in my mind the Slate is a one trick pony or one hit wonder... You get it, you BT as much as you can without maxing it, and then you pay it off and eventually PC it to something more useful
The plain jane BOA Plat... has some low apr possibilities.. No guarentees but.. also.. the BOA Plat seems to consistently get BT offers....... So if i had a choice. id probably go for the BOA plain card over the Slate..