Diodes and CMOS 4060 (14-stage counter)
The conection of those diodes is called wired AND, i.e. the output (= common node after the diodes) is high only when both inputs are high.

The current flowing through the outputs is Ub / R4 = 3V / 100kOhm = 0.03 mA which is well below the max. output current this IC can sink.

So: yes, it's common. It is not unhealthy.

(What you might have in mind is that currents caused by voltages above the supply voltage of the IC and even more by voltages below GND at any input or output must be avoided. This is, however, not the case here)