while some pages in the zabbix frontend have a separate column to show entity count (configuration -> host groups), some do not show any count (configuration -> templates).

table cell entities also get limited (by default to 50 entries), thus it would be useful to show how many entities are in each cell - possibly by appending something like this to the cell contents :

(total: 785)

specifying total would be better, as it would prevent the user from trying to count the entries in the cell already to determine the total count.