Why don't some shops and restaurants have accessible doors?

As someone who often walks around town with a son with service dog in tow or with a partner using a walker, I notice, a lot more than I used to, when shops and restaurants don’t have accessible power-operated doors. I asked the City of Charlottetown Planning Department about this, and the Building Inspector helpfully replied with a reference to the 2010 National Building Code, Section 3.8 Barrier Free Design:

Except as provided in Sentences (6) and (12), every door that provides a barrier-free path of travel through an entrance referred to in Article 3.8.1.2., including the interior doors of a vestibule where provided, shall be equipped with a power door operator that allows persons to activate the opening of the door from either side if the entrance serves:
   a) a hotel,
   b) a building of Group B, Division 2 major occupancy, or
   c) a building of Group A, Group B, Division 3, Group D or E major occupancy more than 500 m² in building area.
(See Appendix A.)

Pulling this apart, power doors are required for:

• Hotels;
• Buildings “of Group B, Division 2 major occupancy”: these are hospitals, nursing homes, and similar facilities;
• Buildings “Group A, Group B, Division 3, Group D or E major occupancy more than 500 m2 in building area”: this includes everything from cinemas to libraries to banks to shops and restaurants.

The places I’m concerned about most often fall in the third item–shops, restaurants, etc.–and the reason that the examples I cited to the Planning Department as lacking accessible doors are, it seems, exempt under the “more than 500 m²” provision.

Five hundred square meters, or 5381 square feet, is a pretty large space (our house is 2400 square feet over two floors). This means that most shops and restaurants would fall under the amount of space, and not be required to have an accessible door.

This doesn’t mean, of course, that such spaces can’t install a power door, and I encourage everyone, in their comings and goings, to encourage shops they patronize to improve accessibility in all ways, including this one.

(The City of Charlottetown is migrating from the 2010 National Building Code to the 2015 National Building Code; the Building Inspector confirmed with me that nothing has changed with regards to the 500 m² cut-off in this regard).