Pure speculation on my part, but I think they were/are likely carrying a lot of debt from UFAs actions in recent years and that it likely played a large part in the closing of the chain.
UFA bought Wholesale in 2008 and later that same year they bought 15 Sportsman's Warehouse locations in the US and rebranded them as Wholesale Sports. Sportsman's Warehouse was strapped for cash at the time and the remaining stores were forced to apply for chapter 11 in 2009. UFA closed their first US store in 2011 and they ended up selling the remaining locations by 2013. At the same time, they were expanding in Canada, opening locations in Edmonton, Lethbridge, Winnipeg, Saskatoon, Kamloops, Prince George and West Kelowna. Excluding Edmonton and Winnipeg, the rest of the cities they opened stores in only have a combined population of about 650,000 people. Kamloops, for example, only has about 90,000 people and they already had a specialized flyshop as well as a general outdoors competitor in Surplus Herbies. My point is, they likely lost money on the US deal and even if they did grab a lot of the market share in those smaller cities in Canada it would still likely take quite a bit of time to generate enough revenue to pay off the setup costs. A lot of this expansion was done when the price of oil was high and the Alberta economy seemed invincible. I'd guess that UFA management likely expected their "flagship stores" in Alberta to grow and to be able to shoulder a lot of burden with respect to servicing this hypothetical debt. Unfortunately, when the price of oil fell and the Alberta economy took a hit... Closing the entire chain rather than trying to sell it or restructure seems like too drastic a move, considering they opened their last store in 2014 and the media reported that they saw a 9% reduction of sales in 2016 when compared to 2015, unless they were already close to the brink. Again, this is 100% speculation so take it with more than a grain of salt.
It is a shame and I wish the employees well, but hopefully this will create an opportunity for someone other than the big box stores to step in and fill the void.