Well, they do have to give you the option to just take your money back if you can arrange better alternatives. But I do believe they need to help you find accommodations for that as well. At least according to the EU portal about flight passenger rights:

Assistance in the event of cancellation

Airlines should offer you and provide assistance free of charge while you wait. In the event of travel disruption, you should make yourself known to the airline, to avoid a situation where you have to make your own arrangements. Airlines should also ensure, where available, that accommodation is accessible for people with disabilities and their service dogs. The assistance to be provided includes:

Refreshments
Food
Accommodation (if you are rebooked to travel the next day)
Transport to your accommodation and return to the airport
2 telephone calls, telex, fax messages or emails

If assistance is not offered and you paid for your own meals and refreshments etc., the airline should reimburse you, provided the expenses were necessary, reasonable and appropriate. You should keep all receipts for this purpose. You only have the right to assistance as long as you have to wait for re-routing, under comparable transport conditions, to your final destination at the earliest opportunity or a return flight.

In exceptional cases, the airline may decide to limit or decline assistance if it would cause further delay to passengers waiting for an alternative or a delayed flight.

So I get that it's annoying for the ground staff being used as a human shield for anger, but you ARE supposed to "make yourself known" and there is clearly an implication of some back-and-forth to agree on what's possible. Given what the expectation being set is I'm not sure I'm ready to blame passengers for being angry when getting less than expected. If you're sleeping on the floor somebody wasn't ready to deal with cancellations as well as they should have been.

Also, fax and telex being explicitly listed there is delightfully 80s.

For the record, I once got stuck at an airport in the US for maybe five extra hours during a layover (the longest delay I've had that wasn't just a warning before I got to the airport) and they did buy me a Burger King meal while I waited, so it's not like this isn't done. I think the scenarios we all visualize where this is a problem are mass cancellations in emergencies where tons of flights are grounded all at once and hundreds or thousands of people need help.

On the one hand I get how those are impossible situations, but they also happen regularly, so the protocols for them should probably be better than they are.