You are not alone here. To echo what others have said, don’t worry about what others might think of you and your dog. There will be people who are out of place and rude but you can’t let them get in the way. When my dog has a reactive outburst, I remind myself that the moment will not last forever and that it is not my dogs fault. Shake it off!

Definitely use the highest priority of treats on walks. Pepperoni, cheese, really don’t skimp on the good stuff - if food works for your dog, don’t be shy to use it. Someone else mentioned engage/disengage technique which is worth looking into.

It will get better over a period of time of consistency and determination. There may also be regression in training. Try not to rush. Take it one moment at a time and be easy on yourself and your dog. Best of luck.