Prosecution is not based on whether and act is "thinkable" or not. It needs evidence. And if evidence comes up against a poor person, him being poor does not mean he shouldn't be interrogated or prosecuted.
And, what evidence gives you the conviction to assume that he is being made the scapegoat for "crimes of Dr Talwar". There is no evidence against him as yet, except for a theory made up by noida police which falls flat on its face.
Please wait for the investigation to be over before making rigid convictions. And, though there shouldn't be injustice to a person because he is poor, if a person is involved in crime he shouldn't also be let off just because he's poor.
