I don't think I fully understand the answer in this conversation:
A: すみません, みせのまえですから.
It seems to me that the answer states that it is OK to park in front of the store. But what is the role of すみません and から? If we label すみません as "I am sorry" and から as "because", then "I am sorry, because you can park in front of the store" doesn't make sense. Does すみません mean something like "I am sorry, but no" in this sentence?
I am also curious why the answer simply uses みせのまえです. Shouldn't it be something like みせのまえにいいです?