My youngest is now 5 and this is my 3rd year doing this, as of end of March. Generally my kids are good, especially when I tell them ahead of time that this is for work, so they have to be very well behaved and not saying anything about the work.
I also tend to bribe them with time doing something we don't get to do very often, like going out to a park. After a while, you will have a good idea how they will behave in certain situations and which shops are appropriate to bring kids along.
All that said, I have done one restaurant shop that specifically says that it is for 2 adults only, but the schedulers were selling it as kid appropriate (the restaurant is family friendly), but the report is not to mention the kids at all. We also had to pay separately for the kids meals. The waitresses never questioned it, but it felt awkward asking for the kids' meal separate from the adult meals.