First you should know that the Muslim prayer can be performed within specific time frames. So after the call for prayer (azhan) which initiates the beginning of the time frame a Muslim has -based on the views of the schools of jurisprudence (so called madhhabs)- a more or less long time period in which he may perform his prayer.
Praying in a mosque is highly recommended. There are a few madhhabs which go so far saying that not praying in congregation is a sin, but the maliki's which are the leading school in Morocco are not among these madhhabs. Nevertheless it is sinful to hear the call of the prayer and not answering it by going to the mosque.
Also note that going to the mosque is much more a due for men than for women, you may even find some Muslim countries where finding a woman in a mosque may appear strange (as far as I've been told in Yemen it is rather not common to expect women entering a mosque).
As to the Jumu'ah (Friday) prayer it is a due on men who are able to pray according to specific conditions, for example for a traveling person it wouldn't be considered as obligatory, but recommended. And it must be performed in congregation (in a mosque).
So based on all of this any men who is able to pray should have followed the call for prayer or in worst case took his time to pray the fard (obligatory) prayer in a mosque or for example his shop etc. or prepare himself and go to pray the Jumu'ah in a close big mosque in which this prayer is held, as jumu'ah prayer doesn't make sense without a gathering so it must be done in congregation.
But what you've observed might be typical sinners which you may find in any religion.