Received refusal for parents on 22 Oct and on 23 Oct we reapplied and received Stamped Visa on 29 Oct....but now they have access to travel for next 10 Yrs.
i have read the thread where a businessman applied TRV for a trade fair he got passport after couple of days when trade Fair was passed. at the port of entry immigration staff inquired about his visit. he replied i got visa after the trade fair date so now i came for tourism. they refused his entry and sent him back and asked him to get the TRV for tourism again.
this is just for reference better to check it with canadian embassy or relevent authorities.
Thanks of your valuable inputs, today I received my parents Visitor Visa. @Ksavier Thanks for your advise to reapply asap with better answers/proofs to the refusal grounds.