I hope I'm not going to far off-topic, but quantum mechanics does not say things stop existing when observed.
First of all "observed" has nothing to do with concious beings. It's a shorthand for a complicated processes known as environmental entanglement or decoherence.
Quantum mechanics says that physical systems do not have single fixed values for every quantities like they do in classical mechanics. For example they don't have a fixed location, but are instead spread over a few locations.
However certain quantities end up becoming classical or fixed at one value due to interactions with environment. For example in a table the atoms do not have a fixed location, but the table itself does, since it interacts constantly with the air and light from outside. Quantities get fixed into single values by their interaction with the environment.
If the table was removed from all interactions, for example by sealing it in a complete dark room, with no air and freezing to near absolute zero (this has to be done, since otherwise the table would interact with the kinetic energy of its own atoms) then after about a few hundred years the table would begin to "blur" and its location would stop possessing a single definite value.
However the table always exists, there is always matter present and that matter has a fixed total mass, momentum and angular momentum. Quantum mechanics does not effect quantities like this, the amount of mass is always fixed at a single value, like classical mechanics.
The quantities that are effected, simply become indefinite, i.e. not possessed of a single value. In the presence of interactions with the environment they become definite, if you remove the environment they become indefinite again.
The only reason "observation" is used, is because often in quantum mechanical experiments we concentrate on quantities that don't tend to be affected by the environment, such as the positions of atoms. In these cases the kinetic energy (temperature) of atoms in our experimental equipment essentially forms an environment for the atoms. Hence our experimental equipment ends up fixing atomic quantities into single values during their interactions with the atoms.
"Collapse" was the old term for atomic quantities being fixed to single values and we tended to see this happen during "observations". Hence the old phrase "observation cause collapse", but in reality this is just a special case of the fact that the presence of thousands of interactions with some kind of environment causes any system to assume fixed values.