This question is born more out of sheer laziness than curiosity, but preparing two marinaded meat dishes the other day (Char Su pork and pork vindaloo), it struck me that I could have saved myself a lot of washing up if I marinaded the meat in the plastic packaging they came in. Would there be any danger of chemicals leaching from the plastic if either a yoghurt or acidic marinade was used? The meat would be stored in the refrigerator for a maximum of 24 hours. 
Low and high density polyethylene (PE) and polypropylene (PP) are the two common plastics used in food packaging and food storage containers. Your Ziploc/Rubbermaid etc. containers and bags are chemically identical to most flexible packaging materials used for meat. Polystyrene (PS) in the both the extruded foam and rigid forms is common as well for meat trays. All are considered chemically compatible and inert to most aqueous food acids: CP Lab Safety LDPE Chemical Compatibility Chart - https://www.calpaclab.com/ldpe-chemical-compatibility-chart/ CP Lab Safety Polypropylene Chemical Compatibility Chart - https://www.calpaclab.com/polypropylene-chemical-compatibility-chart/ Dutcher PE, PP, PS Compatibility Chart (PDF) - https://www.dutscher.com/data/pdf_guides/en/CCTPPA.pdf Note that the LDPE table lists 'severe effect' with citric acid, but does not specify concentrations like for acetic acid and shows excellent to good compatibility with fruit juices, cider, and malic acid. The Dutcher chart has fewer entries regarding food and food acids at specific concentrations. All were tested at ambient temperature, so you can expect even less reactivity under refrigeration. Additives may be used in these plastics (UV protection, antioxidants for stability, plasticizers for flexibility) and should all be rated for food contact. They're typically oil-soluble organic molecules, and generally won't leach into aqueous solutions; however, they may leach into oil-based, high fat, or alcohol-containing marinades. Pthalates in polyethylene terepthalate (PET) are a plasticizer of concern, though in my experience PET is rarely seen in North America in my region PET is rare other than in specialty beverage bottles and imported Japanese beverages.  References and Further Reading: Characterization of plastic packaging additives: Food contact, stability and toxicity. Meriem Cherif Lahimer, Naceur Ayed, Jalel Horriche, Sayda Belgaied. https://doi.org/10.1016/j.arabjc.2013.07.022 Food Safety Focus (60th Issue, July 2011) – Incident in Focus: Plasticisers and Food Safety. Melva Chen. https://www.cfs.gov.hk/english/multimedia/multimedia_pub/multimedia_pub_fsf_60_01.html 