I like the coffee shop for its social aspect as much as I do for the caffeine. It's usually crowded, and there never seems to be enough tables. I've met many people there by asking, "Can I sit with you until a table opens up?" Nothing like sitting with interesting people, and hearing their stories while they're amp'ed-up on caffeine. =)
On days when I have the Bug, I bring along some children's books. (I've learned a lot about children's books over the years.) It used to be I was the only one, but now I see other parents doing the same.
One guy even shared saying, "My wife saw you reading to your son. Now she makes me bring books for our daughter." =)
Normally the Bug is friendly and engaging. Many have commented on his ability (for such a little kid) to carry on conversations with adults.
[One lady mentioned taking her similarly-aged son to weekly speech-development sessions after talking to the Bug .. cuz her son wasn't yet making full sentences.]
But during our reading-time, he doesn't want to engage with anyone, nor does he want me to converse with friends. He has even placed his hand over my mouth and said, "Don't talk, dada. Read!" (sounding more like 'ReeEEED!')
Of course, I feel bad for the nice folks who stop by our table, merely wanting to engage him for a minute and say hello .. especially after they haven't seen him for a while. They don't know it's not personal, but merely bad timing.
Earlier this week, I noticed a couple who seemed enchanted with him as he made the rounds, saying hello to different friends (seated at different tables), showing off his new pirate shirt (that his dada got for him).
That was a first. (Normally I have to park & knock before I can see him in the morning.) 
