PeterLI wrote:

Each jurisdiction is different and you can be charged with and convicted for misdemeanors/ felonies by taking property (computers) without permission.

More BS.
In all of the vast wide Internet go find us one example where trash picking was prosecuted as a Felony.
Note: Being against a Federal Law does NOT make something a Felony.
In the US the federal government defines a felony as a crime punishable by death or imprisonment in excess of one year. If punishable by exactly one year or less, it is classified as a misdemeanor.
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Outside of local and state ordinances, consensus is likely the worst you would receive is a ticket for littering and the like or perhaps some harassment from law enforcement. Civil law outlines some substantial culpability for retrieval of proprietary information from garbage for the purpose of gaining a business advantage:
Tennant Company v. Advance Machine Company

Tennant and Advance are competitors in manufacturing and marketing floor cleaning equipment. From fall 1978 through spring 1979, certain Advance employees rummaged through the trash in a dumpster behind Tennant's western regional sales offices in California. The raids uncovered some confidential sales information that George McIntosh, an Advance employee, forwarded to other Advance salesmen and to company officers.

gdjacobs wrote:

for the purpose of gaining a business advantage:

That is basically Industrial Espionage.
Really doubt anyone collecting dated, old, dead computers is going to be accused of that.
Especially if they don't run a competing business.
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For the most part bins in unlocked, unposted, unfenced publicly accessible areas around buildings (including apartment complexes and office buildings) or bins that are 'out to the curb' at private homes aren't going to get you in trouble.
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Law Enforcement (that isn't stupid) does not want Laws against that because it would mean anything THEY collect from those areas can not be used as evidence unless they got a search warrant first.
They want the liberty to pick through that trash without notice to find nasty little secrets (like the meth lab in the kitchen or the bomb factory in the garage) so they can get a warrant to look inside the building.
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