Im sorry but I really dont see how having a bottle in the house can affect the mothers confidence about breastfeeding.
I breastfed all my children and plan to do so with this one too but like you wanted to have bottles there just in case.
For those days you really are shattered and want DH to take over for a bit, those days you can go have a bit of time to yourself with a girlfriend and not having to worry about been home at certain time to feed.
I use Tommee Tippee closer to nature and the ones I got the other day are also BPA free so that was an added advantage.
Good luck in your choice