Thank you for replying. I can use either Chrome, Safari, or Firefox - but I get the same result - which is a mixed bag at best. I've had this issue with Apple products for a series of Macbooks - have lost count on how many I've owned.
Of course there is no problem with open, non commercial wifi, or even passworded wifi nor my Apple Airport products and most other brands.
It only seems to occur when I use one such a Fred Meyer (Kroger), Starbucks and my community college, where I'm hoping to be presented with a sign in screen - to either accept terms or to enter a username or password. Many times, at places such as Starbucks, I can't get the screen to appear.
My ethernet works fine, no problems joining a network, either at the university I attend or through a router at home. And the performance seems fine - I've not clocked it, but I am satisfied with the connection speed, so never thought to test the speed.