When you are in a group of happy people you absorb their energy. And when these happy people are in nature - it is doubly useful. I used to ignore going to the park. I spent a lot of time working and developing. But this is not the right way. Over time, you need to learn to relax. Any person needs rest and it is desirable that this holiday is accompanied by movement. If you spend time on the couch in front of the TV - then this is not a rest. The best holiday is an active vacation in nature.
I like to see people walking in the park. In this there is something special that creates an atmosphere of relaxation. You're right - a good feeling is contagious. But alas, and a bad feeling is more infectious. It is useful and bad people use. Those people who play on the feelings of people and encourage them to commit bad deeds. When people are in a crowd - they turn into a thoughtless and lightly manipulated organism.
But do not focus on the bad. Your photos called me to go out and take a walk in the park amidst the happy people and trees. We need to enjoy the moment.
Thank you!