Actually, it is only your visits to the opthamologist that are covered by the government medical plan. I get tax rebates on my contact lenses, but I suppose they are considered "cosmetic" so they are not covered. Laser surgery is also considered cosmetic so you pay the bill yourself. Once you get to the point of being legally blind then I think everything is covered for you, but up until then you pay for lenses & frames yourself and then get a tax deduction on the lenses at the end of the year.
The Canadian medical system is like every other socialised system in the world right now -- it's slowly crumbling to pieces.
Just the other night I was saying to my flatmate and my sister (an obstetrician) that I would happily pay more than my C$54 a month if it meant that the system would be improved, but my flatmate, who makes $80,000 a year, got all upset and thought that we are already paying too much. So my sister told him that from the outside he's got no idea how hard the hospitals are trying to save money now -- the doctors used to get free batteries for their pagers, if the battery died they just went to the nurses station and got another -- now they have to buy them themselves, which saves the hospital $12-24 per year per doctor!
It does seem that the Canadian system will soon have to switch to a two-tiered system, which will be quite sad. As I said the other night, if they think that saving $12 on batteries will help, I don't see why they don't increase the monthly fee to $60 (at least for those with salaries over $25k/30k) - a $6 raise per person should give the system a huge boost.