I think capital gains tax obviously plays a role in how people invest. On the other hand, to the extent that you deal with stocks or other assets that pay income, that income is declared every year on your return and is taxed to the extent that it's taxable. A problem that arises very often is if you had held a security for about 50 years and your records don't exist anymore, you will probably have to go to the V-day date in 1972 to fix your capital gains tax. Very often, unless you have an accountant who keeps track of each one of your assets in stocks and bonds and the original cost in Canadian dollars, sometimes the records are just not there.
By and large, in Canada, I believe most people in these types of assets pay a capital gains tax. To what extent they pay it when they sell a cottage where they haven't kept all the repair bills, etc., that's a different matter and it's much more complicated.
As an aside, I think you should also address at some point the RRSP, RRIF situation, where, in effect, if I invest in stocks, when I take the money out I don't pay any capital gains tax, but I pay 100% tax instead of the 50%. This makes it pretty prohibitive to invest in stocks in that kind of investment.