Slow streaming at a sporting event has everything to do with money, and just about nothing to do with bandwidth.  The bandwidth could be made available, but why would a carrier do that to accommodate a spike in traffic during an event.  In addition to that, some of the issues are with servers, not bandwidth, so it becomes more of a complex issue.  And you, the user, have no idea if it's a server issue or a bandwidth issue.
Carriers have the bandwidth.  It costs them money to turn it on/increase it.  And they're not going to do that without being able to make money on it, which, btw, I am fine with.
You want more bandwidth while you're traveling?...the issue isn't that you can't get it, it's that it's expensive.  For awhile, I have two hotspots, one on ATT, the other on Verizon, so that I'd rarely, if ever, be without at least ONE connection, and I'd rarely be limited by bandwidth.  I don't need that now, so I dropped the Verizon plan.
Jim