I needed to go on Google Earth to check some geography in detail.
If you draw a line due east from Toronto, it passes over 150 miles of Lake Ontario, then over Snow Ridge and McCauley 45-60 miles later.
If you draw a line WSW-ENE from Hamilton, it passes over 185 miles of Lake Ontario (maximum fetch) to Watertown, and the high Adirondacks over 4,000 feet are 100 miles later on that line. Big Tupper ski area is just west of the high peaks with elevation range 2,000 - 3,000.
Anyone know how much snow Big Tupper gets? Based on local comments above I would conclude that either:
1) The due west-to-east winds are much more frequent than WSW-ENE, or more likely,
2) Lake effect snow is common 50 miles downwind from Lake Ontario but not so much 100 miles downwind.
A scan of the capital of "lake effect," Japan, reinforces theory #2 above. Niseko is less than 15 miles from the Sea of Japan. Almost all of the noted powder areas are within 50 miles of the Sea of Japan with at least 3,000 feet of orographic uplift, and the places 15 miles inland get more snow than the ones 50 miles inland.
Then you have Mt. Bohemia, which sits on a peninsula 5 miles from Lake Superior, with exposure over 80-130 miles of water to the west, north and east.
The Adirondacks are rarely affected by lake affect snow due to the orientation of the lakes
So I'll say the Adirondacks are rarely affected by lake affect snow because they are not close enough to Lake Ontario. This would not have occurred to me without looking it up on Google Earth.