@Bronek Kozicki
You do not need a reason to own a shotgun. A shotgun licence is a "shall issue" if there are no reasons not to. There is no limit on how may you can own once you have a licence, no limit on the amount of ammunition, and you do not have to prove they are being used regularly.
A firearm licence (rifles, shotguns that can hold more than 3 shells) are "may issue" and you need to have a reason to own them, belong to a rifle club and regularly use them. You have to state which calibres you wish to own, are limited to buying only what you've asked for and are limited on the amount of ammunition you can hold.