"Ooh, I'll take ten!"
― Homer Simpson
Vendors refer to mobile units in the game which wander paths and periodically issue bonuses, usually around every 8 to 12 hours. Bonuses vary between several types:
Vendors are usually a bonus gift received with purchase of a qualifying amount of Diamonds (D), the premium currency.
Once purchased vendor cards appear in inventory. Clicking on a card will place the vendor in the zoo, where it will be dispatched from the front gate and begin wandering pathways, similar to employees. Unlike employees vendors can be clicked on, returned to inventory, and 'sold' for a whopping 0 ZD. With the exception of the Mascot, there does not appear to be any limit on the type or amount of vendors that can be added to a zoo.
When a vendor is ready to issue a reward a star will appear above his head. Clicking on the star will cause the vendor to pause for a few seconds, after which time a line of text will appear above him stating what the bonus was. This information is also recorded in the game log in case you miss the text. Clicking on or hovering the cursor over a vendor when a star is not present will tell you how long until the next bonus is ready. Vendors always start at the front gate when logging in or returning to your zoo from visiting a friend's zoo.
Clicking on a vendor also allows you to cycle through all the vendors in your zoo using the green arrows that appear on either side of the vendor's title. This is a convenient function if you have a large zoo with many vendors.
Bonuses appear to scale according to level. XP and ZD rewards tend to be between the 100 - 800 range, though they may be both higher and lower.
Employee cards consist of 7 day employee teams for all types of employees.
Trading card pieces can be highly varied and often include unusual ZD animal cards, which are rare but not always worth a lot on a practical level. Occasionally highly valuable diamond animal trading cards are received. Plants and decoration cards are also common, similar to what you receive from daily boosters or completing friendship tasks. Bonus types are completely random each time a star is clicked.
Though not a vendor in the true sense of the word, the mascot does issue rewards of ZD or XP every 12 hours. The mascot was introduced on January 29, 2014 as a bonus gift with any purchase of 100 or more Diamonds. On February 5th, with the kick-off of the 2-year anniversary campaign, the price was reduced to any purchase of 12 or more Diamonds. The Mascot was the first of this type of unit in the game. It has remained available ever since with a purchase 12 or more Diamonds. Only one Mascot can be placed in a zoo.
The Ice Cream Vendor was the second of its kind in the zoo, available from March 12th to April 2nd, 2014, with any purchase of 100 Diamonds.
The Hot Dog Vendor was available from April 23rd to May 13th, 2014, and was the third vendor introduced to the game. It was a bonus gift with any purchase of 100 Diamonds.
The game's fourth vendor, Mr. Barbecue was included as a gift with any purchase of 100 Diamonds from July 16th to August 6th, 2014.
Santa is the game's fifth vendor, available during the 2014 - 2015 holiday season as a free gift with any purchase of 100 diamonds.