https://peekage.com/widgets/6c8f1494-2eaf-4841-9a87-3f3deafd5925 -click lets do it and answer the questions to get three Free Pouches of Hartz Delectables Licking Cat Treats.

Download the Buddies app for iOS or Android and  register. You can also get an extra 200 point with referral code: CDAVIEBFFB at registration.
They give you 700 points when you register, which is enough for a Free bag of Blue Buffalo Dog Treats. To get those go to rewards, then redeem. It might take a minute or two for the 700 points to show up.
–Update– It was working slow before, but seems to be loading better now.

https://www.surveymonkey.com/r/FreeCollar -fill out the form to get a Free YOOS Dog Collar.

https://zignature.com/free-sample/ -fill out the form to get a Free Zignature Dog Food Sample. –Update – still available

https://r71aavfvqnd.pro.typeform.com/petalumasamples -fill out the form to get a Free Petaluma Sustainable Dog Food Sample.

https://karmapetfoods.com/kollective -fill out the form to get a Free Karma Kollective Kit. It includes a t-shirt, leash, and free bag coupon. First 1,000.

https://www.confidenceeq.com/terms/item/13-free-sample-offer-fill out the form to get a Free Confidence EQ Horse Product Sample .

https://meridianpetfood.com/request-samples/ -fill out the form to get a Free Meridian Dog Food Sample.

https://www.petpads.net/sample/request? -fill out the form to get a Free PetsWorld Training Pad Sample.