Welcome to the community!
Firstly, Fido does not generally price match on an individual basis. However, there have been occasions where they have offered special promotional plans in response to promotional plans offered by other providers. You can view Fido's current promotions here.
I understand some other providers' offers can be appealing. However, one thing to keep in mind when comparing different offerings it to make sure you're comparing similar services. Shaw Mobile may offer a cheaper plan, but it's important to remember that they are also only a regional provider. Their prices might only reflect their lack of National coverage.
I'm not trying to sway your decision in any direction. Just don't think that the only differentiator is cost. Often, you're just not paying for what you're not getting. Only you can decide what service best suits your needs.
Hope this helps 😀