You are correct. Very odd. Never noticed it. It is a bad regulation.
http://www.albertaregulations.ca/fishingregs/
Province-wide maximum possession – All fish kept from any lake or stream, from any Watershed Unit, count as part of the province-wide maximum possession that must not be exceeded. The maximum number of fish you may have, including fish at your home and fish caught under a special harvest licence, for each
game fish species or group of species is listed below:
Trout and Arctic Grayling – 5 in total, combined of:
0 bull trout (native to Alberta);
2 Northern Dolly Varden (stocked in Chester Lake only);
1 golden trout;
2 Arctic grayling;
3 lake trout;
5 cutthroat trout;
5 rainbow trout;
5 brown trout;
5 brook trout.
Mountain Whitefish – 5 in total.
Walleye and Sauger – 3 in combined total.
Northern Pike – 3 in total.
Yellow Perch – 15 in total.
Lake Whitefish and Cisco (Tullibee) – 10 in combined total.
Goldeye and Mooneye – 10 in combined total.
Burbot (Ling) – 10 in total.
Lake Sturgeon – 0
Non-game fish – no restriction on the numbers kept.
The edible flesh of legally kept game fish must not be wasted, destroyed, spoiled or abandoned (
this does not apply to burbot).