Sorry, yes we have a disability pension and an old age pension equivalent called CPP (Canadian Pension Plan). If you have an employer, you pay half the required contributions and your employer pays the other half. If you are self-employed, you make the whole contribution.
We also have EI (Employment Insurance) which is another wage deduction but not mandatory if self-employed. If you lose your job for reasons of no fault of your own, then you can apply to receive unemployment benefits for a certain amount of time while you seek new employment. I think the max is 12 months and it is based on your employment history (how long you were consecutively employed) which personally I think is too long. It gets abused regularly, similar to welfare benefits...
My opinion on cash work is that there are certain acceptable limits. I've openly admitted to my accountant that I will continue to accept cash payments for certain work. Small businesses with high wage overhead have to consider this an option to offset huge tax incursions. Also, cash jobs are a convenient way to provide cash (undeclared) bonus' to employees. This is only recommended when you know your employees very well, like or as family. It has it's risks, but most often for small businesses here in Canada the CRA will simply just demand the back-taxes on any revenue that you're caught hiding. You will also be placed on a "red-flag" list and risk auditing, but generally they don't come down as hard as people think or expect unless you're a repeat offender. They understand that the existing system takes into account for cash dealings, therefore enabling them. One of the those vicious cycle things.
The company I work for would average 3 to 5 cash jobs per year, with maybe 1 or 2 being over $5000. I've also seen half-and-half jobs, half cash and half "on the books". This usually pertains to smaller jobs like garages, sheds, outbuildings, etc and usually reserved for family or folks they know.