Those programs are all doing work on your computer. Therefore you install them on your computer. The only reason to deny access to a website for other browsers

Those programs are all doing work on your computer. Therefore you install them on your computer. The only reason to deny access to a website for other browsers is to get your own native software on the machine of the user. If Google would deny access to a Google website with browsers other than Chrome, everybody would be mad at them. There are a lot of angry posts about Googles websites being less optimized for Firefox than for Chrome. Outright banning alternative browsers is what is happening here.