At which point every two-bits shadowrunner, clever gang members or petty thief can enter by that lightly guarded doors with little fuss by just lifting one of these cards.
What you say makes sense in RL but not much in SR where crime is so high, where a whole class of criminal for hire has evolved along with a market large enough to insure your competitors can access their services.
I would expect instead that at the very least there would be :
- A pass card...
- ...linked to a biometric ID (probably just fingerprint for most places, these are pretty cheap)
- A camera.
- The use of the card would create a signal for the guard on duty at the front desk who would then peek at the security feed to see who is there and also look at the schedule before buzzing in the crew if everything checks out. Otherwise he can challenge them over the interphone for clarifications.
These measures are cheap to implement are for cheap place. Barely cost more than just the pass card alone but increase security a lot. From that minimum, your imagination can run wild if there is a stronger incentive for security. Starting of course with some magical counter-measures.
These measures are not that hard to circumvent if you have a good hacker, good planning and perhaps also access to good disguises (Mage with illusion or fancy MI style disguise). But they do make access through the back door roughly as tough as through the front door.
Most importantly, it suffice to keep the riff-raff out, which a simple pass card wouldn't in the context of SR. I figure security in SR should always be at least good enough to keep to riff-raff out, even in a modest business, or else the losses due to criminal activities would be too significant and the insurance premiums alone would put you out of business.
Also, if deficient or nearly absent security is the norm for most businesses, as in RL, then there is little incentive for the runner economy to develop as it did. The crime scene would then look pretty much like our own.